# WILLOW GROVE NAVAL AIR & AIR RESERVE STATION
> **Administrative - Formal** · FY2005 · — · —
## Case
- **Activity ID:** `135709`
- **Case Number:** 03-2005-0045
- **Type:** Administrative - Formal
- **Lead:** EPA
- **Outcome:** —
- **Penalty assessed:** —
- **Cost recovery:** —
- **Compliance action $:** —
- **Multimedia (multi-env):** —
## Defendants
- WILLOW GROVE NAVAL AIR & AIR RESERVE STATION (complaint) (settlement)
## Summary

Naval Air Station Joint Reserve Base, Willow Grove, Horsham, PA - On December 15, 2025, EPA concurred on the final Action Memorandum for a large-scale groundwater pump and treat system for PFAS sources areas on the Navy side of Willow Grove.  The Navy had previously conducted two successful pilot studies in these areas. The PFAS treatment system will consist of treatment with GAC and single-use ion exchange resin with final discharge to Park Creek. The public is generally in support of this action, but there were concerns about flooding at Park Creek and potential drawdown of nearby potable groundwater, both of which have been addressed by the Navy. The Navy also built in additional capacity of the system in anticipation of possibly expanding extraction as part of the long-term remedy and/or treating groundwater from the adjacent Biddle Site.  We expect an Air National Guard Action Memorandum to pump and treat groundwater on the Biddle side sometime in 2026.  




On June 27, 2005, Region III signed a Federal Facility Agreement for Naval Air Station Joint Reserve Base (NAS JRB) Willow Grove, in Horsham, PA.  The Federal Facility Agreement was entered into and signed by EPA, the Department of the Navy, and the Pennsylvania Department.  The Federal Facility Agreement is entered into pursuant to the Comprehensive Environmental Response, Compensation and Liability Act ( CERCLA ), 42 U.S.C. 9620. 

OU-2

THE SUSPECTED SOURCE OF CONTAMINATION AT OU-2 IS A SPILLAGE OF WASTE

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*Source: [EPA ECHO](https://echo.epa.gov/) · AI Analytics · CC0 1.0*